Reanimation is not a proper term used by the game, this page merely groups together vaguely similar traits and units that can be then described as "reanimation".

A number of spells and abilities can reanimate the undead. This page lists these spells and abilities, as well as the special national undead that can be summoned by certain nations.

A basic rule of thumb is that most reanimated undead are mindless troops; usually with 15 Cold Resistance, 25 Poison Resistance, and with at least the traits Need not Eat, Never Heals, and Inanimate.

Generally, most reanimated undead can be grouped into 2 categories: Longdead and Soulless.

• Longdead are also known as skeletons; they are usually resurrected warriors and so are often armed with weapons and armor. They have Attack and Defense stats similar to a trained human, but usually have barely more than half the hitpoints of their living equivalent. Notably, they usually have Spirit Sight and Pierce Resistance.
• Soulless are also known as zombies; they are raised from the corpses of civilians as much as warriors, with lower than normal Attack and Defense stats relative to both cases. They also usually have higher strength and more hitpoints than their living equivalent. Notably, they are usually Undisciplined and do NOT have Darkvision or Spirit Sight.

• Unlife Damage: Units killed by this effect will spawn a new Soulless.
  • Shade Beast's Reanimating Bite deals this type of damage
  • The Construction 6 Two handed Weapon Ivory Bow and the Construction 8 Artifact One handed Weapon Twin Spear both deal this type of damage
  • The spells Bolt of Unlife, Blast of Unlife, and Vortex of Unlife all deal this type of damage
  • How does this choose what type of Soulless to spawn?

• Reanimation Buff: Units killed while under the effect of this buff will rise again for their own side and continue fighting as Soulless with any magic paths and/or commander status intact.
  • The spell Life after Death applies this effect to all non-mindless friendly units.
  • The effect can be applied to but will fail to activate for: Undead, Immortals, Demons, Inanimates, creatures that are inherently Ethereal, Pretenders, and most kinds of Animals. There are also exceptions on a unit by unit case, as seen on here: Loggy's Misc Notes

• Reanimator : Units killed by this unit have a chance equal to the value of their killer's Reanimator trait to spawn an ally of the killer. This is usually a Soulless, but can be something else if the unit also has the "raiseshape" trait.
  • In the base game, there are 2 units with this trait that use it to create Soulless: Mound Fiend and Gorilon - Heliophagus

• Reanimator Priest : A commander with this ability can spend a turn to reanimate a variable amount of undead, depending on their Holy level and the Nation that owns them. For more information, see the section on the Priestly Reanimate order further down.
  • EA Lanka and MA Sceleria have recruitable commanders with this ability
  • MA Ermor and LA Lemuria provide all priests they own with this ability for as long as they are owned
  • MA Asphodel and LA C'tis provide all undead priests they own with this ability for as long as they are owned

• Reanimator2: A commander with this ability will passively raise this many corpses per month as Soulless. This ability has no icon, is normally called Reanimator just like the Raise on Kill effect but is called Reanimator2 here just to differentiate, and is currently only used on God Vessel.

• Reanimation Bonus : A commander with this ability produces as additional amount of troops when reanimating. This ability has two different values, a Priestly reanimation bonus and a Magical reanimation bonus.
  • MA Nazca's recruitable commanders of Mallqui Priestess, Mallqui Priest, and Royal Mallqui have this ability with an equal value for their priestly/magical bonus
  • MA Nazca's Manco-Ocllo - First Couple hero, and EA/MA/LA Mictlan's Mictlipoctli - King of Legends hero both have this ability with an equal value for their priestly/magical bonus
  • 6 pretenders and Bune - Ice Devil, who all lack any Holy paths, have this ability with a 0 for priestly bonus
  • The Construction 4 Miscellaneous Item Amulet of the Dead and the Construction 8 Artifact Crown The Crown of Despair both provide this ability
  • What spells and orders does this affect again? Like I remember it working for Longdead and Longdead Horsemen but not Lictors or Ghouls.

complete list, add more detail

• Reanimate Longdead Horsemen: MA Sceleria and MA Ermor
  Reanimating priests with 3 or higher can summon Longdead Horseman.
• Reanimate Lictors: MA Ermor
  Reanimating priests with 4 or higher can summon undead Lictors.
• LA C’tis Tomb Priests: LA C'tis (undead priests)
  Reanimating priests can summon Soulless/Longdead of C’tis, 2 or higher can summon Tomb Wyrms and 3 or higher can summon Tomb Chariots.
• Reanimate Manikin: MA Asphodel
  Reanimating priest can summon the various types of Manikin.
• Reanimate Supayas: MA Nazca
  Reanimating priest of this nation will summon Supayas.
• Reanimate Greek Ghosts: EA Therodos
  Reanimating priest of this nation will summon Greek ghosts.
• Reanimate Ghosts: LA Lemuria
  Reanimating priest of this nation will summon ghosts.

Nations that have no special lesser undead summon the following types of undead:

• Longdead: Longdead, Longdead, Longdead, Longdead, Longdead, Longdead
• Soulless:

The following nations will summon special types of undead when reanimating the appropriate type:

EA Ulm
EA Ulm's longdead have higher-damage weapons than most undead.

• Longdead: Longdead, Longdead, Longdead
• Soulless: N/A

The Monkey Nations (EA Lanka, EA Kailasa, MA Bandar Log, LA Patala)
The undead Bandar are notable for having unusually high hitpoints and strength.

• Longdead: Longdead Markata, Longdead Vanara, Longdead Vanara Warrior, Longdead Vanara Warrior, Longdead Bandar, Longdead Bandar Warrior, Longdead Bandar Warrior
• Soulless:

EA Hinnom and MA Ashdod
Hinnom and Ashdod reanimate giant longdead with very high damage and moderate hitpoints, making each summoning of longdead much more valuable than it would be for other nations.

• Longdead: Longdead Rephaite, Longdead Rephaite, Longdead Rephaite
• Soulless: N/A

• Loggy's Longdead and Soulless reverse engineering notes